List of top Plant Sciences Questions on Molecular Biology

If you have 5 nucleotides, say A, T, G, C and X, how many triplet codons you could have formed from it ?

Which one of the following is NOT a path of genetic information flow as per the modern Central Dogma of Biology ?

Along with JD Watson, Francis Crick and Maurice Wilkins, Rosalind Franklin also contributed significantly towards the development of double helical structure of the DNA. All but Rosalind Franklin was awarded with the Nobel Prize. The reason for not awarding Nobel Prize to Roslind Franklin was -

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : DNA polymerase can synthesize DNA in the 5' to 3' direction.
Reason R : DNA polymerase can synthesize DNA in the 3' to 5' direction.

In light of the above statements, choose the correct answer from the options given below:

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: The mode of DNA replication is semi-conservative in nature.
Reason R: One of the DNA strands is synthesized continuously, while the other is synthesized discontinuously.

In light of the above statements, choose the most appropriate answer from the options given below:

Which of the following amino acids initiates protein synthesis in all organisms?

Match the Following:

Match the following:

Match the following:

The subunits of 80S ribosome include

Given below are two statements
Statement I: Self-replicating, circular, extrachromosomal DNA present in bacteria is known as Plasmid
Statement II: Copy number of Plasmids is fixed in a bacterial cell
In light of the above statements, choose the correct answer from the options given below:

Match the following scientific discoveries and techniques in List I with their corresponding scientists in List II:

List I
A. Polymerase Chain Reaction
B. Penicillin
C. Bacillus anthracis
D. Pasteurization
E. Smallpox Vaccine

List II
I. Robert Koch
II. Kary Mullis
III. Edward Jenner
IV. Alexander Fleming
V. Louis Pasteur

Ribosomes are composed of which of the following macromolecular components?
A. RNA
B. Protein
C. Glucose
D. DNA

Chloroplasts are present in the cells of which of the following organisms?
A. Fungi
B. Algae
C. Plants
D. Animals

If Meselson and Stahl's experiment on the mode of DNA replication is continued up to the sixth generation in bacteria, the ratio of Heavy strands 15N/15N: Hybrid15N/14N: light strand 14N/14N containing DNA in the sixth generation would be-

As per the general model, the order of the activities in the DNA replication in E coli from the beginning to the end is:
A. Enzyme ‘primase’ synthesizes the ‘primer RNA’
B. Single-strand binding (SSB) proteins bind to the separated single strands and stabilize them.
C. DNA gyrase and DNA helicase unwind the complementary strands of DNA in the origin of replication (Ori C).
D. After digesting the RNA primers, the ‘Okazaki fragments' are joined together by the enzyme ‘ligase’.
E. Synthesis of DNA starts and goes continuously in the ‘leading strand’ and discontinuously in the ‘lagging strand’
Choose the correct answer from the options given below:

To resolve a parental dispute, the Honourable Judge ordered for DNA-fingerprinting of the child. The probable DNA finger prints of the child would be-

Which of the following are NOT chain initiation codons
A. UAA
B. UAG
C. UGA
D. AUG
E. GUG
Choose the correct answer from the options given below:

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: Plant disease symptoms need not harbor the pathogen propagules always
Reason R: Crown gall harbors Agrobacterium tumefaciens
In light of the above statements, choose the correct answer from the options given below

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: In the Watson-Crick model of DNA, each turn of the helix is the length of 10 base pairs.
Reason R: Each complete turn of the double-stranded DNA helix is 3.4 \r{A long.
In light of the above statements, choose the most appropriate answer from the options given below:

Heterosis cannot be fixed, if it is obtained through-
A. Apomixis
B. Balanced lethal system
C. Development of F1 hybrid
D. Development of synthetic variety
E. Vegetative propagation
Choose the correct answer from the options given below:

The gas used in gas delinting of cotton seeds is-

The horn development in sheep (horned sheep) is a suitable example of which of the following events?